Hydrothermal Syntheses, Crystal Structures, and Properties of a Novel Class of 3,3‘,4,4‘-Benzophenone-tetracarboxylate (BPTC) Polymers

Abstract

Three novel BPTC complexes, (H(2)BPTC)(4,4'-H(2)bpy)H(2)O (1), [Cd(2)Cu(HBPTC)(2)(mu(2)-4,4'-bpy)(2)(4,4'-bpy)(2)(H(2)O)(2)](n) (2), and [Co(3)(HBPTC)(2)(mu(2)-4,4'-bpy)(3)(H(2)O)(4)](n).2nH(2)O (3) (BPTC = 3,3',4,4'-benzophenone-tetracarboxylate and bpy = bipyridine), were hydrothermally synthesized. Complex 1, which is obtained as a coproduct during the syntheses of complexes 2 and 3, features a 2-D layered strong hydrogen bonding network with 2-fold interpenetration. Complex 2 has an unusual 2-D double-layered motif, which is linked together by Cu atoms in a face-to-face manner. It exhibits nanosized channels filled by 4,4'-bpy ligands. Three six-coordinated Co atoms in 3 are interlinked by HBPTC ligands to form a 2-D grid structure, which is further sustained by rigid 4,4'-bpy ligands into a 3-D open framework similar to CdSO(4) with the BPTC moieties situated in the tunnels. The thermal stabilities of complexes 1-3 were examined. The photoluminescence properties of complexes 1-2 and temperature-dependent magnetic susceptibility for 3 were also studied.